#game-container {
    width: 400px;
    height: 600px;
    background-color: #2c3e50;
    position: relative;
    overflow: hidden;
    box-shadow: inset 0 0 30px rgba(0,0,0,0.8);
}

#game-canvas {
    width: 100%;
    height: 100%;
    display: block;
}

#hud-score, #hud-level {
    background: rgba(0,0,0,0.5);
    padding: 5px 10px;
    border-radius: 5px;
}